A decision on whether dam breaching
is necessary — or whether increased barging of fish downriver would do
as well in recovering Snake River salmon populations — could still swing
on what researchers can learn about smolt transportation’s “D value.”
Newer studies indicate that the D
value (differential delayed transportation mortality) is not as high as
was once thought, according to Chip McConnaha, manager of program and analysis
and evaluation for the Northwest Power Planning Council.
